Hi somu,
yes, i renamed all pages,and clean solution means,in solution explorer only na,i mean right click on project name,then click on clean ha?if is this right process,i did it,and again am getting the same error.

oh ok,i will try it.Thank you for your suggestions.
I have another problem,that is,i have one page which is containing hyperlinks,but when i am executing this page,hyperlinks are jumped to another place,means which place i provided for hyper links they are not there,when am executing.what should i do?